Effective Model Approach to the Dense State of QCD Matter

Abstract

The first-principle approach to the dense state of QCD matter, i.e. the lattice-QCD simulation at finite baryon density, is not under theoretical control for the moment. The effective model study based on QCD symmetries is a practical alternative. However the model parameters that are fixed by hadronic properties in the vacuum may have unknown dependence on the baryon chemical potential. We propose a new prescription to constrain the effective model parameters by the matching condition with the thermal Statistical Model. In the transitional region where thermal quantities blow up in the Statistical Model, deconfined quarks and gluons should smoothly take over the relevant degrees of freedom from hadrons and resonances. We use the Polyakov-loop coupled Nambu--Jona-Lasinio (PNJL) model as an effective description in the quark side and show how the matching condition is satisfied by a simple ansatz on the Polyakov loop potential. Our results favor a phase diagram with the chiral phase transition located at slightly higher temperature than deconfinement which stays close to the chemical freeze-out points.

8 pages, 4 figures; Talk at International Workshop on High Density Nuclear Matter, Cape Town, South Africa, April 6-9, 2010

References in corpus (7)

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Cited by in corpus (5)

• QCD and strongly coupled gauge theories: challenges and perspectives
• Non-congruence of the nuclear liquid-gas and deconfinement phase transitions
• High-Energy Phase Diagrams with Charge and Isospin Axes under Heavy-Ion Collision and Stellar Conditions
• Exploring criticality in the QCD-like two quark flavour models
• Color superconductivity in the Nambu Jona-Lasinio model complemented by a Polyakov loop